I have no idea how to word this, so I'll just say it. I've had a similar experience in the past where I just felt bleh and kept having thoughts like this. I also had pretty bad anxiety, so that didn't help. But no matter how dark it feels, there's always an end to it. I can't explain it, but the bleh feeling just stops.
There are treatments if you need it, and it's nothing to be ashamed of. Some people need glasses to see, and that's completely fine. Same with therapy or medicine for depression. Personally, I use both. I also know several people who have gone through this, but they're all doing great now.
I guess what I'm trying to say is you're not alone in this. Never have been and never will be, and there will always be help available. Suicide hotline is 988 if you ever need it.
(Sorry if that sounded cheesy, I'm a cheesy person)
=)